Hi,I recently designed a sort of "library" in order to make easier to play exact notes on arduino with the buzzer.
I included the frequencies of the notes (pleasant to be heard) with #defines .
I then defined the value of the BPM ( you can modify it obviously) and according to that I defined the note values
( the most commonly used ones).
With this defines you can easyly play a note with the command "tone" like this:
tone(pin, note, duration)
eg:
tone(8,LA3,Q);
delay(1+Q);
the delay is important because thanks to that the note doesn't overlap possibly with the successive ones.
(the "1+" is one extra millisecond that i usually put to separate notes but you can avoid it if you prefer the notes to be continuous.